How do I catch up on programming terms for game development?

I'm trying to dive into game development, specifically with Unity and C#. However, I feel lost when it comes to the terminology. In many tutorials, I notice that terms pop up in Visual Studio Code as they type, but I don't have that feature working for me. I'm not sure what the auto-filled suggestions are called or how to access them. Is there anywhere that categorizes programming terms like "public," "using," "void," "int," or "UnityEngine.UI"? I would love a comprehensive resource that breaks down these terms and explains what they do, as I feel like I'm just a beginner struggling to unravel the complexities of the programming language.